CVE-2020-11608: 
Linux Kernel vulnerability analysis and mitigation

An issue was discovered in the Linux kernel before 5.6.1. The vulnerability affects drivers/media/usb/gspca/ov519.c, which allows NULL pointer dereferences in ov511_mode_init_regs and ov518_mode_init_regs functions when there are zero endpoints, also known as CID-998912346c0d. The vulnerability was discovered in early 2020 and fixed in kernel version 5.6.1 (Kernel Changelog).

The vulnerability stems from missing endpoint sanity checks in the OV51x USB Camera device driver. The driver did not properly validate device metadata, specifically failing to verify the presence of at least one endpoint before accessing the endpoint array. This could lead to NULL pointer dereferences when attempting to access endpoint descriptors. The vulnerability has been assigned a CVSS v3.1 Base Score of 4.3 (MEDIUM) with vector: CVSS:3.1/AV:P/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (NVD Database).

When exploited, this vulnerability could allow a physically present attacker with a specially constructed USB device to cause a denial-of-service condition through system crash. In some cases, it might also potentially lead to privilege escalation (Ubuntu Advisory).

The vulnerability was fixed in Linux kernel version 5.6.1 by adding proper endpoint sanity checks. The fix ensures validation of endpoint presence before accessing the endpoint array. Multiple Linux distributions have released security updates to address this vulnerability, including Ubuntu, Debian, and others. Users are advised to update their systems to the patched versions (Kernel Changelog, Ubuntu Advisory).